Water On -and In- Terrestrial Planets

Nicolas B. Cowan

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arXiv · 1511.04444

Water On -and In- Terrestrial Planets

Nicolas B. Cowan

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Abstract

Earth has a unique surface character among Solar System worlds. Not only does it harbor liquid water, but also large continents. An exoplanet with a similar appearance would remind us of home, but it is not obvious whether such a planet is more likely to bear life than an entirely ocean-covered waterworld---after all, surface liquid water defines the canonical habitable zone. In this proceeding, I argue that 1) Earth's bimodal surface character is critical to its long-term climate stability and hence is a signpost of habitability, and 2) we will be able to constrain the surface character of terrestrial exoplanets with next-generation space missions.

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Nicolas B. Cowan. 2015-11-13. Water On -and In- Terrestrial Planets. https://arxiv.org/abs/1511.04444

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